Which celestial body is considered a "dwarf planet"?

Pluto is classified as a "dwarf planet" due to its characteristics and the criteria established by the International Astronomical Union (IAU) in 2006. A dwarf planet is defined as a celestial body that orbits the Sun, is spherical in shape due to its own gravity, and has not cleared its neighboring region of other objects. Although Pluto has sufficient mass for its gravity to shape it into a nearly round form, it shares its orbital zone with other objects in the Kuiper Belt and has not cleared this region of smaller debris.

Unlike Pluto, Venus, Mars, and Mercury are classified as full planets. They satisfy the criteria of being in orbits cleared of their neighboring celestial bodies, allowing them to be categorized as major planets rather than dwarf planets. This distinction is why Pluto remains the most notable example of a dwarf planet within our solar system.